August 2023

The Perception Of Change
There's so much we could all benefit if we evolve our new designs and product developments.
Editorial By J. Martins

  As I always like to say: I know that I know nothing, but I'm always learning. (Plato would agree if he had said it)

Unfortunately, in the life of a magazine editor I have long learned that there is never enough time to just study and learn. I strongly admire people who have devoted their whole career to study, research, and publish what they learned (many times combined with teaching). That's what I always like about attending conferences, where here and there you come across people and work that shake the foundations of our knowledge and understanding.

That was the case recently, when I — together with our technical editor Jan Didden, and a good number of audioXpress authors — attended one of the opening sessions of the 154th Audio Engineering Society (AES) International Convention, held at Aalto University in Espoo, Helsinki, Finland, from May 13th through 15th. The panel session, titled "Towards an Objective Understanding of High-End Audio" — expanded in the actual event to Hans van Maanen, Milind N. Kunchur, Joshua Reiss, Menno van der Veen, Mike Turner, and Jaime Angus-Whiteoak. The first intervention by distinguished professor Milind N. Kunchur, from the University of South Carolina, basically set the tone when he attempted to summarize in the allotted time his recent work, "The Human Auditory System And Audio" (©Elsevier 2023) accepted manuscript.

Each sentence in his brief introduction exploring his extensive work in psychophysics, auditory neurophysiology, and high-fidelity sound reproduction was basically enough to merit a session in itself. He stated up front that evaluation of audio performance needs to take into account "the complexities and intricacies of the human auditory system" and "be based on a better biological foundation." Statements about the human auditory system, phase, frequency, and time signal analysis in the time domain, or even brain centers and memory (backed by the extensive bibliography quoted in his research) all have profound implications on the audio industry as we characterize it today. In the audience, distinguished AES Fellows and members of the audio community could be seen jumping on their chairs with excitement!

As described in the conclusions of this work, Prof. Kunchur explained how musical training causes significant cortical changes (shifts the emphasis from the right to the left hemisphere of the brain) and how an extended multiple-pass (EMP) listening protocol facilitates forming a consolidated opinion in durable long-term memory. He further quoted research that found that our brain needs at least 15 seconds to replace the short-term memory during a listening test as the reason why standard blind tests employing short-segment comparison (SSC) of back-to-back brief stimuli often fail (Thus, judging sound quality takes time!)

In his "Implications for Audio" conclusions, he also explains why very high and even ultrasound frequencies may be audible "at high levels or as part of a complex tone due to mechanisms such as heterodyning," (nonlinear mixing) and bone conduction.

In a remarkable Richard Heyser Memorial Lecture also focused on the human auditory system, titled "The Ear is not a Fourier Transformer," Jamie Angus-Whiteoak, emeritus professor at the University of Salford, reinforced the message about the need to better understand "the unique ways the human auditory system allows us to hear the incredible complexity of the audio signal and how that might affect what we do in the future to improve audio."

I had this extensive research in mind while working on this issue's article about active acoustics and seeing how much academic and scientific work has contributed to the significant progress in this important technology. Among many other sources, I had to go through the extensive and remarkable work of Josh H. McDermotta and the Department of Brain and Cognitive Sciences, at the Massachusetts Institute of Technology, and the (related) extensive work of David Griesinger in this field.

There's so much we could all benefit if we evolve our new designs and product developments always based on the latest scientific research.

My appreciation and thanks to Luigi Agostini, E-coustic Systems project division manager for the EMEA market, for the support in the meeting and interview with Steve Barbar, and coordinating our visit to the amazing DiMenna Center for Classical Music, featured in this issue. Enjoy!

J. Martins
Editor-in-Chief

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